On a naturalist approach to laws of nature, it seems appropriate that the basis, and with it the glueing relations, should be determined a posteriori. How to positively characterize the supervenience base will, in general, thus depend on the direction of future fundamental physics. Any attempt of doing so risks replacement by superior future theories. This fallibility of our metaphysical tenets is, however, an epistemic risk that a naturalist must accept. Let us briefly consider two examples of candidate quantum theories of gravity in order to study, by way of example, how such a supervenience basis may look like. The two examples are causal set theory[1]}; for an introduction aimed at philosophers and an argument that causal sets are significantly non-spatiotemporal, see [2]}. and loop quantum gravity[3]}; for an introduction aimed at philosophers and an argument that spin networks are significantly non-spatiotemporal, see [4]}..
